Devices, systems, and methods for locating magnetic injection fill ports

ABSTRACT

Devices, systems, and methods provide accurate and consistent identification of the center of a magnetic infusion port.

RELATED APPLICATIONS

This application is a continuation of application Ser. No. 12/313,446filed 20 Nov. 2008 (now U.S. Pat. No. 8,171,938), which claims thebenefit of Provisional application Ser. No. 61/004,402, filed 27 Nov.2007.

FIELD OF THE INVENTION

This application relates generally to magnetic injection fill ports usedwith tissue expanders and like expandable devices.

BACKGROUND OF THE INVENTION

Tissue expanders are commonly used in breast reconstruction and scarrevision surgery. Tissue expanders are placed beneath muscle or skin toexpand the tissues and allow for the stretching, recruitment andcreation of new skin and tissue. The tissue expander is filled withsaline solution through a peripheral infusion port.

Conventionally, the infusion port is now integrated on the tissueexpander with a magnetic metal backing both to allow for magneticidentification of the expander port and to prevent perforation orrupture of the expander by preventing the needle from puncturing thedeep surface. Chemotherapy and other medication infusion devices alsohave metal backed ports for similar reasons.

A representative magnetic infusion port is disclosed in Rehder et alU.S. Pat. No. 6,588,432, which is incorporated herein by reference.FIGS. 1A and 1B show a magnetic infusion port 10 integrated on a tissueexpander 18, as disclosed in the Rehder '432 Patent. As shown in FIGS.1A and 1B, a needle guard member 12 is positioned spatially from and onthe opposite side of the infusion port body 14 from where the needle 16enters, to prevent the needle from puncturing the infusion port 10 andentering into the tissue expander 18 of the patient. A magnetic material20 is affixed in the infusion port body outside the infusion port cavity22 and the needle guard member 12. The magnetic material 20 ispositioned outside the infusion port cavity 22 so that its placementdoes not interfere with the normal and proper insertion of a needle 16into the infusion port cavity 22. The magnetic material 20 may be anyshape or dimension, and made of any magnetically detectable material.

For example, the magnetic material 20 may include samarium cobalt orneodymium iron boron, a combination thereof or like material. Theoutermost perimeter of the magnetic material 20 is spatially alignedwith or within the perimeter of the region of the infusion port 10 intowhich the needle is injected, thus demarcating this region as a targetfor the needle 16. The magnetic material 20 also has a surface treatmentto prevent it from corroding, such as a nickel coating or the like, andis completely enclosed in a polymer, such as a silicone elastomer or thelike, to protect it from environmental exposure.

As further described in Rehder '432 Patent (and as shown in FIGS. 2A and2B), to locate the infusion port 10, a magnetic detection probe 24 isused. The magnetic probe 24 has a polarity opposite to the polarity ofthe magnetic material 20 of the infusion port that faces the infusionport cavity 22. The magnetic probe 24 is therefore attracted to themagnetic material 20 of the port 10. In use, the probe 24 is scannedacross the region of skin containing the port 10. The probe 24 willpoint to the magnetic material 20 and thereby pivot from a tiltedposition (when on one side of the magnetic material 20), to an uprightposition (when over the magnetic material 20, to an opposite tiltedposition (when on the opposite side of the magnetic material 30). Whenscanned along an x-axis, and then along a y-axis, the tilt of the probe24 establishes at least four points of reference A, B, C, D creating acoordinate system. The location for inserting the needle is at theintersection I of two line segments L1 and L2, each defined by a pair ofthe reference points A and B/C and D established by two passes of thedetection probe 24. This intersection I is where the magnetic infusionport 10 is located and where the needle 16 should enter.

FIGS. 3A and 3B show a typical detection probe 24 in use in associationwith a magnetic infusion port 10 on a tissue expander 18. FIG. 3A showsthe probe 24 in a generally vertical position, pointing to the magneticmaterial 20 of the infusion port 10, indicating that it is magneticallyaligned over the magnetic material 20 of the infusion port 10. FIG. 3Bshows the probe 24 in tilted position, indicating that it is spaced to aside of the magnetic material 20 of the infusion port 10. The directionof the tilt points to the location of the infusion port 10.

The detection probe 24 used to locate the infusion port 10 adds to theexpense of the expansion device 18. Also, in use, the detection probe 24can be cumbersome to handle. The probe 24 can often stick and lead toinaccurate needle placement. This can, in turn, lead to the accidentalperforation of the expander 18 if the needle is not directly introducedinto the port 10 or otherwise perforates the silicone shell of theexpander 18 at the wrong angle. If the expander 18 is not fully expandedfor an adequate time when the expander 18 is prematurely punctured, thismay necessitate a less than optimal result or another unnecessaryoperation to replace the expander 18.

Accurate and precise location of the infusion port 10 as close to itscenter as possible is critical. Often times the expander 18 is placedvery deep to the skin with overlying muscle or fatty tissue. The deeperthe expander 18 is in the body, the more difficult it is to identifywith the probe 24.

SUMMARY OF THE INVENTION

The invention provides devices, systems, and methods for theidentification of the center of a magnetic infusion port.

One aspect of the invention provides a system including an infusion portand a port finder. The infusion may have a magnetic portion, themagnetic portion may have a first surface may have a first magneticpolarity and a second surface may have a second magnetic polarity. Theport finder may have a first surface and a second opposite facingsurface, the first surface may have a first magnetic polarity and thesecond surface may have a second opposite magnetic polarity, the portfinder may have a center hole extending through the port finder from thefirst surface to the second surface.

The system may include a sleeve. The sleeve may have an interior cavitysized and configured to receive the port finder. The sleeve may have anopening adjacent the interior cavity, the opening being sized andconfigured to receive the port finder.

The sleeve may have a sticky back side. The back side of the sleeve mayhave a cover that can be peeled back to expose the sticky material. Theback side of the sleeve includes an anesthetic.

The system may include a flexible member coupled to the port finder. Theflexible member may be a string.

The port finder center hole may be sized and configured to allow passageof a needle through the center thereof. The port finder center hole maybe sized and configured to allow passage of a marking apparatustherethrough.

Another aspect of the invention provides a method including the steps ofproviding a magnetic infusion port, providing a magnetic port finder,and implanting the magnetic infusion port.

The method may include using the magnetic port finder to locate themagnetic infusion port.

The method may include inserting a needle through the center of themagnetic port finder into the magnetic infusion port.

The method may include marking the location of the magnetic infusionport on the through the center of the magnetic port finder.

The method may include removing the magnetic port finder and inserting aneedle into the magnetic infusion port at the marked spot.

The method may include providing a sleeve, inserting the magnet into thesleeve, and using the magnetic port finder to locate the magneticinfusion port.

The method may include providing an adhesive surface on at least onesurface of the sleeve.

The method may include inserting a needle through the center of themagnetic port finder into the magnetic infusion port.

The method may include removing the needle from the magnetic infusionport and removing the magnet from the sleeve, the sleeve remaining toserve as a bandage.

The method may include inserting a needle through the center of themagnetic port finder into the magnetic infusion port.

The method may include removing the magnet from the sleeve and insertinga needle through the sleeve into the magnetic infusion port.

The method may include removing the needle from the magnetic infusionport and allowing the sleeve to remain as a bandage.

The method may include placing an anesthetic on the backside of thesleeve.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B show a prior art magnetic infusion port of the typeshown in U.S. Pat. No. 6,588,432.

FIGS. 2A and 2B show the use of a prior art magnetic probe inassociation with the magnetic infusion port shown in FIGS. 1A and 1B.

FIGS. 3A and 3B show a conventional magnetic probe in use with aconvention magnetic infusion port.

FIG. 4 is a perspective view of a port finder that embodies features ofthe invention.

FIGS. 5A and 5B are side views, partly in section, showing the magneticalignment of the port finder shown in FIG. 4 with a conventionalmagnetic injection port.

FIG. 6 shows the passage of a needle through the center opening of theport finder shown in FIG. 4, when in magnetic alignment with a magneticinjection port as shown in FIG. 5B.

FIGS. 7A and 7B show the use of a marker to mark skin in the centeropening of the port finder shown in FIG. 4, when in magnetic alignmentwith a magnetic injection port as shown in FIG. 5B (FIG. 7A), followedby the removal of the port finder and passage of a needle through themark (FIG. 7B).

FIG. 8 is a view of the port finder shown in FIG. 4 carried on alanyard.

FIG. 9 shows the port finder shown in FIG. 4 in various sizes toaccommodate magnetic injection ports of different sizes.

FIG. 10A/B shows the port finder shown in FIG. 4 carried in a sleeve.

FIG. 11 shows a side view of the sleeve of FIG. 10.

FIGS. 12A/B and 13A/B show the passage of a needle through the centeropening of the port finder and sleeve shown in FIG. 10, when in magneticalignment with a magnetic injection port.

FIG. 14 is a side view, partly in section, showing the magneticalignment of an alternative embodiment of a port finder with aconventional magnetic injection port.

FIG. 15A/B shows the port finder of FIG. 14 carried in a sleeve.

FIG. 16 shows an additional alternative embodiment of a port finder.

DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

Although the disclosure hereof is detailed and exact to enable thoseskilled in the art to practice the invention, the physical embodimentsherein disclosed merely exemplify the invention that may be embodied inother specific structure. While the preferred embodiment has beendescribed, the details may be changed without departing from theinvention, which is defined by the claims.

FIG. 4 shows a port finder 30 that embodies features of the invention.The port finder 30 comprises a disc having generally flat, oppositefacing surfaces 32 and 34. The port finder 30 is made from a magneticmaterial 36 polarized so that the facing surfaces 32 and 34 presentopposite magnetic North and South poles, as indicated in FIG. 4.

As illustrated, the port finder 30 is shaped to generally correspondwith the shape of the magnetic material 20 of the infusion port 10,which is typically circular.

The port finder 30 includes a center hole 38. The hole 38 is sized to atleast allow passage of a needle 16 (see FIG. 6). The hole 38 isdesirably sized to allow passage of a marker 40, to mark a location onthe skin underlying the hole 38(see FIG. 7A).

As FIGS. 5A and 5B show, and as before described, the magnetic material20 of the infusion port 10 is polarized to present either a Northmagnetic-pole or a South magnetic-pole in the direction of the infusionport cavity 22. In the illustrated embodiment, the North magnetic-polefaces the infusion port cavity 22, but the reverse can be true. Magneticattraction between the North magnetic pole of the material 20 of theinfusion port 10 and the opposite South magnetic pole of the magneticmaterial 36 of the port finder 30, will orient the facing surface of theport finder 30 having the opposite magnetic pole (in FIGS. 5A and 5B,facing surface 32) directly over and in alignment with the magneticmaterial 20 of the infusion port 10. The center of the hole 38 of theport finder 30 marks the precise location of the exact or near center ofthe infusion port 10.

In use (see FIG. 6), the physician can pass the needle 16 through thecenter of the hole 38 into the infusion port 10. Alternatively (seeFIGS. 7A and 7B), the physician can use a marker 40 to first mark theskin in the direct center of the hole 38 (FIG. 7A), then remove the portfinder 30, and then pass the needle 16 through the mark to access theport 10 (FIG. 7B).

In an alternative embodiment (see FIG. 8), the port finder 30 can beattached to a lanyard 42, string or other material and allow forrepeated confirmation of the center similar to a pendulum. Left free toswing and pivot on the lanyard 42, the port finder 30 will automaticallyorient itself with respect to the magnetic material 20 of the infusionport 10, to mark the placement of the needle. The lanyard 42 can also beused for holding or hanging or storing the port finder 30.

As FIG. 9 shows, the port finder 30 can be variously sized andconfigured to generally correspond with the size and configuration oftypical magnetic field of the port finder 30 should be maximized to theextent possible. Often times, the ports 10 and expanders 18 may be verydeep beneath the skin. The deeper they are placed the more difficult tofeel and localize the port accurately, and the less the magnetic fieldof the magnetic material 20 of the port 10 will be at the surface of theskin, so the use of a stronger magnet for the port finder 30 will be ofgreat benefit.

The magnetic fields of the magnetic material 20 of the infusion port 10and the opposite magnetic field of the port finder 30 accurately andconsistently place the center hole 38 of the port finder 30 at thecenter or near center of the infusion port 10. All surgeons, nurses orpatients that surgically place or access tissue expander ports, orchemotherapy or drug infusion ports, will benefit from the use of theport finder 30. The port finder 30 allows for more specific and accurateneedle access to the port 10 and decreases the chance of accidentalexpander or implant puncture and potential unnecessary surgery.

The system may also include a sheath or sleeve 40 as shown in FIGS. 10and 11. The sleeve 40 is sized and configured to allow the port finder30 to be placed within the sleeve 40. The sleeve 40 preferably includesa interior cavity 48 sized and configured to receive the port finder 30and an opening 50 sized and configured to receive the port finder 30.The opening 50 may take any form known in the art, including, but notlimited to a slot. Preferably the port finder 30 is inserted in thesleeve by sliding the port finder 30 through the opening 50.

The sleeve 40 is preferably clear and may be made of a plastic orsilicon material. The sleeve 40 is preferably disposable. The sleeve 40may be provided with adhesive 42 on one exterior surface thereof. Theadhesive 42 may be of any type known in the art. In this manner, thesleeve 40 may stick to the skin directly and sterilely over the portfinder 30 and port 10. The sleeve 40 may further be provided with aremovable backing member 44 covering the adhesive 42. The backing member44 may be of any material known in the art including, but not limited toplastic or paper. It is further contemplated that a topical anestheticsubstance 46 may be placed on the side of the sleeve 40 contacting thepatient's skin. The anesthetic substance 46 may be applied to the sleeve40 by the physician, or may be applied to the sleeve 40 during themanufacturing process.

In use, the sleeve 40 may be placed on the port finder 30 as shown inFIG. 10. The backing member 44 may be removed and the port finder 30 maybe used to locate the port 10. The physician may then insert a needle 16through the port 10 as shown in FIGS. 12 and 13. The port finder 30 maybe removed from the sleeve 40 either before the needle 16 is insertedthrough the port 10 or after the needle 16 is removed from the port 10.It is contemplated that the sleeve 40 may be left in place to act as abandage once the needle 16 is removed. In an alternative embodiment theport finder 130 may have a generally spherical configuration as shown inFIG. 14. The spherical port finder 130 preferably includes a center hole38 sized and configured for passage of a needle therethrough. Thespherical port finder 130 is made from a magnetic material polarized toprovide a magnetic North pole and an oppositely disposed magnetic Southpole as indicated in FIG. 14. This “Bulls Eye Port Locator” may be wellsuited for small port locations such as with the LapBand (R) product byAllergan or chemotherapy ports.

It is contemplated that a sleeve 40 made of plastic or silicone asdescribed above may be provided around the spherical port finder 130 anda string or lanyard 42 could be coupled to the sleeve 40 as shown inFIG. 15. The sleeve 40 preferably includes an interior cavity 48 sizedand configured to receive the port finder 130 and an opening 50 sizedand configured to receive the port finder 130. The opening 50 may takeany form known in the art, including, but not limited to a slot.Preferably, the port finder 130 is inserted into the sleeve 40 bysliding the port finder 130 through the opening 50.

As described above the magnetic material 20 of the infusion port 10 ispolarized to present either a North magnetic-pole or a Southmagnetic-pole in the direction of the infusion port cavity 22. In theillustrated embodiment of FIG. 14, the North magnetic-pole faces theinfusion port cavity 22, but the reverse can be true. Magneticattraction between the North magnetic pole of the material 20 of theinfusion port 10 and the opposite South magnetic pole of the magneticmaterial 36 of the spherical port finder 130, will orient the facingsurface of the spherical port finder 130 having the opposite magneticpole (in FIGS. 5A and 5B, facing surface 32) directly over and inalignment with the magnetic material 20 of the infusion port 10. Thecenter of the hole 38 of the spherical port finder 130 marks the preciselocation of the exact or near center of the infusion port 10.

It is further contemplated that the port finder 230 could have ahemispherical configuration as shown in FIG. 16. The hemispherical portfinder preferably includes a center hole 38 sized and configured forpassage of a needle therethrough. It is further contemplated that thehemispherical port finder 230 may be used with a sleeve 40 as describedabove.

The foregoing is considered as illustrative only of the principles andtechnical features of the invention. Furthermore, since numerousmodifications and changes will readily occur to those skilled in theart, it is not desired to limit the invention to the exact constructionand operation shown and described. While a representative embodiment hasbeen described, the details may be changed without departing from theprinciples and technical features of the invention.

1. A system for locating an implanted infusion port comprising: aninfusion port, the infusion having a magnetic portion, the magneticportion having a first surface having a first magnetic polarity and asecond surface having a second magnetic polarity; and a port finder, theport finder having a first surface and a second opposite facing surface,the first surface having a first magnetic polarity and the secondsurface having a second opposite magnetic polarity, the port finderhaving a center hole extending through the port finder from the firstsurface to the second surface.
 2. The system of claim 1 furthercomprising a sleeve.
 3. The system of claim 2 wherein the sleeve has aninterior cavity sized and configured to receive the port finder.
 4. Thesystem of claim 2 wherein the sleeve has an opening adjacent theinterior cavity, the opening being sized and configured to receive theport finder.
 5. The system of claim 2 wherein the sleeve has a stickyback side.
 6. The system of claim 5 wherein the back side has a coverthat may be peeled back to expose the sticky material.
 7. The system ofclaim 2 wherein the back side of the sleeve includes an anesthetic. 8.The system of claim 1 further comprising a flexible member coupled tothe port finder.
 9. The system of claim 8 wherein the flexible member isa string.
 10. The system of claim 1 wherein said port finder center holeis sized and configured to allow passage of a needle therethrough. 11.The system of claim 1 wherein said port finder center hole is sized andconfigured to allow passage of a marking apparatus therethrough.
 12. Amethod comprising: providing a magnetic infusion port; providing amagnetic port finder; implanting the magnetic infusion port.
 13. Themethod of claim 12 further comprising using the magnetic port finder tolocate the magnetic infusion port.
 14. The method of claim 13 furthercomprising inserting a needle through the center of the magnetic portfinder into the magnetic infusion port.
 15. The method of claim 13further comprising marking the location of the magnetic infusion port onthe through the center of the magnetic port finder.
 16. The method ofclaim 15 further comprising removing the magnetic port finder; andinserting a needle into the magnetic infusion port at the marked spot.17. The method of claim 12 further comprising providing a sleeve;inserting the magnet into the sleeve; and using the magnetic port finderto locate the magnetic infusion port.
 18. The method of claim 17 whereinat least one surface of the sleeve has an adhesive substance thereon.19. The method of claim 18 further comprising inserting a needle throughthe center of the magnetic port finder into the magnetic infusion port.20. The method of claim 19 further comprising removing the needle fromthe magnetic infusion port; and removing the magnet from the sleeve, thesleeve remaining to serve as a bandage.
 21. The method of claim 18further comprising removing the magnet from the sleeve; and inserting aneedle through the sleeve into the magnetic infusion port.
 22. Themethod of claim 21 further comprising removing the needle from themagnetic infusion port; and allowing the sleeve to remain to serve as abandage.
 23. The method of claim 22 further comprising placing ananesthetic on the backside of the sleeve.
 24. A system for locating animplanted infusion port comprising: an infusion port, the infusionhaving a magnetic portion, the magnetic portion having a first surfacehaving a first magnetic polarity and a second surface having a secondmagnetic polarity; and a port finder, the port finder having a firstpole having a first magnetic polarity and a second pole having a secondopposite magnetic polarity, the port finder having a center holeextending through the port finder from the first pole to the secondpole.
 25. The system of claim 24 wherein the port finder has a generallyspherical configuration.